Electric water heater



W. O. SNELLING.

ELECTRIC WATER HEATER.

APPLICATION FILED Auc.24. 1920.

Patented Jan. 3, 1922,

UNITED STATES ra'ran'rv OFFICE.

nnnornrc warm HEATER.

Specification of Letters Patent.

Patented Jan. 3, 1922.

Application filed August 24, 1920. Serial No. 405,744.

To all whomit may concern Be it known that I, WALTER O. SNELLING, a citizen of the United States, residing at Allentown, in the county of Lehigh and State of Pennsylvania, have invented certain Improvements in Electric lVater Heaters, of which the following is a specification.

My invention relates to improvements in water heaters, and more particularly relates to an improved water heater in which an electric current roduced by induction is used as a. means 0 heating a stream of water.

The ordinary forms of water heaters employing wire of high resistance as a heating means are open to objection, because of the readiness with which most forms of resistance wire deteriorate when operated under the severe conditions met with in a water heater. One object of my invention is to provide a means of heating water through the aid of electricity, without the use of wire of high resistance. Another object of my invention is to provide an electrical water heater of reat capacity and flex1- bility, and one whic will efficiently utilize a large percentage of the electrical energy consumed by the apparatus.

The drawing accompanying this specification represents somewhat diagrammatically one form of apparatus embodying the principles of my present invention. 1 is a pipe connected with a source of water supply under pressure, 2 is an orifice valve connecting pipes 1 and 3. 4 is a coil of pipe forming a secondary of transformer 14, this coil of pipe being preferably of copper-or other metal of high electrical conductivity. 5 is a connecting rod, for the purpose of short-circ-uiting the two ends of coil 4, and should also be preferably made of metal of high electrical conductivity. 6 is a short length of pipe connecting coil 4 with an expansion tube 8, this expansion tubebeing made in the form of a long inverted U, held firmly in place by a clamp 7. 9 is a pipe leading from expansion tube 8 to any place at which a supply of hot water may be desired. 10 is a valve attached to pipe 9, and 11 is a connecting pipe leading off from pipe 9, and communicating with a bellshaped vessel 12, provided with a diaphragm 8 and supply pipe 9, to valve 10 and to any connected pipes for supplying hot water. Assuming valve 10 to be closed, a uniform condition of pressure is very quickly reached through the entire system of piping, and

this pressure causes diaphragm 13, insulator 22 and contact 21 to assume a certain definite position, whichnormally is suchthat a slight gap is left between contact point 21 and contact point 19. No current will flow throughw'i're 17, coil 15, wire 18,contact point 19, contact point 21, or wire 23, as long as such gap exists between contact points 19 and 21.

If however valve 10 is opened, sons to allow water to flow, the pressure in the system will at once be reduced, the size of the orifice in orifice valve 2 being such as to insure a reduction of pressure occurring whenever a normal flow of water is permitted by the opening of a service valve. This reduction in pressure will cause diaphragm 13 to become depressed, bringing contact points 19 and 21 together, and permitting current to flow through coil 15 of transformer 14. A

very strong current will at once be induced in coil 4 and through connecting rod 5, and the temperature of coil 4 will rise rapidly, heating the water which is passing through it. This heated water will pass on through expansion tube 8, expanding this tube and increasing its length. If the temperature of coil 4 becomes too great the expansion of expansion tube 8'- will become suflicient to again separate contact points 19 and 21, and these contact points will also be separated if the flow of water through the apparatus is shut ofi by closing the valve 10.

In the operation of the device as described,

no current will pass from the source of sup ply 16 through primary coil 15, unless water is being drawn from the supply pipe, and current will at once be shut off when the water is no longer being drawn, and will also be shut oil" it hot water is being drawn so slowly as to. cause too highias temperature lti is ot course evident transformer, in order to' p'revent heat loss'.-

Apparatus constructed in accordance with my present invention is substantially free from fire llilZtLI'(l,'iLll(l is extremely efficient in utilizing electrical energy in the heating of water. Electric current is consumed only when hot water is required, and in proporv tion :to the amountof hot water which is Instead of expansion tube 8',-a solid expansion member lying within coil 4 may be employed, this expansion member serving the same function as expansion tube 8 however, and being used to break the electrical circuit Whenever any desired temperature is reached by the'water. Instead of the bell-. shaped vessel 12 and diaphragm 13, it is of course evident that a bent tube similar to that used in an ordinary pressure gauge may be used, the bending of this tube under differences of pressure being employed to make or break-the electrical circuit through primary coil 15 of transformer 14. It will also be evident that a piston may be substituted for diaphragm 1'3, although the use of a diaphragm possesses certain advantages in freedom from leakage.

Instead of depending upon' the elasticity or resiliency of diaphragm 13 to move contact point 21 on reduction of pressure within the apparatus, it will of course be evident that a-sprin or other suitable member may 'be employet, or two springs operating in' opposite directions upon diaphragm-13 may vbe'used, thei-te'ns'ion of either one or of both of these springs being adjustable. It will also be evident that any of the customary meansof preventing arcing and sparking between contact points 19 and 21 may be employed iii conjunction with the operation of the present device, or an electrical switch may be employed, actuated by contact points 19 and 21, only sufiicient current being-em-' ployed in the circuit comprising contact points 19 and 21to operate such switch, the switch in tu'rn 5 making and brcakin the electrical circuit between the source 0 electrical current 16' and-coil1'5;

It, willaccordingly be evident that many equivalents .may be employed, without departing from the spirit of my present inven-- tion, and accordingly no limitations are to be imposed except such as are indicated'in' the appended claims.

I claim ,as my invention:

. 1; An electrical water heater comprisinga coil .of tubing containing' water forming the secondary winding of an electrical transformer, a coil .of wire forming the primary.

winding of such a transformer, and means for energizing said primary coil operated by the passa e of water through the apparatus.

2. An eilectrical water'heater comprising a coil of tubin containing'water forming the secondary winding of an electrical transformer, means of energizing said primary coil when water passesthrough the appara-- tus, and means for controlling the electrical current energizing said primary coil through temperature changes existing in said coil of tubin of an electrical transtbrmer, a coil of tubing containing water forming the secondary WilldlIl" of such transformer, and means for in electrical water heater comprising a coil of wire fOI'IIllIl" the primary winding control ing the passage of electric current' throughthe primary coil through a change in either the temperature or the pressure of the water in the secondary tubing.

4. An alectrical water heater comprising a coil of tubing containing water, means for inducin' an electric current through such coil, an means for controlling-such electric current throughchanges in; either the tem- I perature or the pressure ofthe water. i

. 5. An electrical water heater comprising a coil of tubing containingwater, and means WALTER o. SNELLING. 

